Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
Let $\mathrm{A}=\left(\begin{array}{ccc}3-\mathrm{t} & 1 & 0 \\ -1 & 3-\mathrm{t} & 1 \\ 0 & -1 & 0\end{array}\right)$ and $\operatorname{det} \mathrm{A}=5$, then
MathematicsDeterminantsJEE Main
Options:
  • A $\mathrm{t}=1$
  • B $\mathrm{t}=2$
  • C $t=-1$
  • D $\mathrm{t}=-2$
Solution:
2970 Upvotes Verified Answer
The correct answer is: $\mathrm{t}=-2$
Hint:
$|\mathrm{A}|=\left|\begin{array}{ccc}3-\mathrm{t} & 1 & 0 \\ -1 & 3-\mathrm{t} & 1 \\ 0 & -1 & 0\end{array}\right|=3-\mathrm{t}=5, \mathrm{t}=-2$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.